Multiple extension apparatus



y 1966 H. K. NANSEL 3,250,182

MULTIPLE EXTENSION APPARATUS Filed Aug. 1, 1963 3 Sheets-Sheet l //vVE/VTOR HAROLD A. NAMSEL A 77'0/9/VE 9 5 H. K. NANSEL May 10, 1966MULTIPLE EXTENS ION APPARATUS 3 Sheets-Sheet 2 Filed Aug.

HAROLD K. AMA/55L May 10, 1966 H. K. NANSEL MULTIPLE EXTENSION APPARATUS3 Sheets-Sheet 3 Filed Aug.

PL 5 ma v 3 MM M Mk V N w K Jr r 0 a k m Z H V/KJ B mmu United StatesPatent 3,250,182 MULTIPLE EXTENSION APPARATUS Harold K. Nansel, Waverly,Nebr. Filed Aug. 1, 1963, Ser. No. 299,428

6 Claims. (Cl. 91-167) 7 This invention relates generally to multipleextension apparatus wherein two or more telescopically mounted extensionsections are involved, and relates also to a fluid control arrangementtherefor.

Although the concept of multiple extension booms is not new, wherein aplurality of telescopically arranged sections are extended one at atime, quite often the control arrangement for the structure isunsatisfactory in that the extension is not always related to the need.Oftentimes, weaker sections of a unit are extended without providing thesupport needed for capacity loads.

It is therefore an object of this invention to provide an improvedmultiple extension apparatus.

It is another object of this invention to provide a multiple extensionapparatus having an improved control structure therefor.

It is a further object of this invention to provide a multiple extensionapparatus having a trio of sections whereinthe second and third sectionsare telescoped into the first section, move out together, and whereinthe third section does not move out of the second section until thesecond section has moved completely out of the first,

section.

Yet another object of this invention is to provide an arrangement forlatching the second section to the first section whereby fluid forretracting purposes flows through a cylinder unit for said secondsection into a cylinder unit for said third section for actuation ofsaid latter unit to retract said third section.

It is still another object of this invention to provide a multipleextension apparatus wherein substantially the entire piston and cylinderstructure for extending and retracting said apparatus is supportedwithin said ap-- paratus.

A further object of this invention is to provide a multiple extensionapparatus, including a control arrangement therefor, which is of extremesimplicity in design and parts, effective in performance, and efiicientin operation.

These objects, and other features and advantages of this invention willbecome readily apparent from the following description, when taken inconjunction with the accompanying drawings, wherein:

FIG. 1 is a perspective, fragmentary view of the multiple extensionapparatus of this invention, shown in completely retracted position;

FIG. 2 is a reduced view of FIG. 1, with a combined second and thirdsection extended;

FIG. 3 is a view similar to FIG. 2, with a third section extended, theentire apparatus extended.

FIG. 4 is a longitudinal sectional view of the apparatus in the FIG. 1position;

FIG. 5 is a longitudinal sectional view of the apparatus in the FIG. 2position;

FIG. 6 is a longitudinal sectional view of the apparatus in the FIG. 3position;

FIG. 7 is an enlarged sectional view taken on the line 77 in FIG. 4;

FIG. 8 is a sectional view of the cylinder units arranged in hydraulicschematic; and

FIG. 9 is a schematic of the hydraulic elements for the apparatus.

Referring now to the drawings the multiple extension apparatus of thisinvention is indicated generally at 10 in FIG. 1, and comprisesbasically a first section 11, a second section 12 (FIG. 2), a thirdsection 13 (FIG. 3), a second section cylinder unit 14 (FIGS. 4-7), athird sec- 3,250,182 Patented May 10, 1966 tion cylinder unit 16 (FIGS.6-9), a latch device 17 (FIG. 4), and a hydraulic circuit indicatedgenerally at 18 in FIG. 9.

The first section 11 is an elongated tube closed at one end 19 (FIG. 5)and open at the other end 21. The closed end 19 has a tongue 22 securedthereto which can be pivotally connected to any structure 23 (FIG. 1),stationary or movable. A pair of longitudinally spaced, diametricallyopposed supporting blocks 24 and 26 are provided with the first section11, and an elongated opening 27 is formed in one side thereof.

The opening 27 is provided for the latch device 17, pivotally connectedat one end 28 to the first section 11, and having the other end 29connected by a spring 31 to an car 32 secured to the first section. Thelatch device 17 has a projection 33 adapted to extend through saidopening 27 and into said first section, due to the bias of said spring31. The purpose for the latch 17 will be described hereinafter.

The second section 12 (FIG. 6) is also tubular, being of a size adaptingits telescopic movement within the first section 11, having a closed end34 and open end 36. Section 12 is also provided with a pair oflongitudinally spaced, diammetrically opposed supporting blocks 37 and38 for the third section 13. An opening 39 (FIG. 5) is formed inthe wallof the second section '12 and is adapted, upon movement of the secondsection 12 to a retracted position, to be aligned with the opening 27.

The third section :13 (FIG. 6) is elongated, tubular, and of a sizeadapting its telescopic mounting within the second section 12. The innerend 41 of the third section 13 embraces the two cylinder units 14 and16, and at the outer end of the third section a pulley unit lifting head42 is mounted. The head 42 is not a. part of this invention and theinvention is not to be'so limited.

The second section cylinder unit 14 (FIGS. 4 and 8) comprises anelongated tubular cylinder 43 closed at its forward end 44 and having apacking gland device 46 at its rear end which is secured to the end 34of the second section 12. A tubular shaft 47, having a, piston 48 on itsinner' end is reciprocally mounted internally the cylinder 43, and whichshaft 47 has a tube 49 mounted concentrically therein.

The forward end 51 of the tube 49 is in fluid communication with theexpansible chamber 52 between the piston 48 and the forward end 44 ofthe second section cylinder. The rear end 53 of the tube 49 is of aT-shape having a pair of fluid passages 54 and 56, and which end 53 issecured to the end 19 of the first section 11 (FIG. 5). The passage 54is in fluid communication with an annular chamber 57 between the tube 49and the shaft 47, and the passage 56 is in fluid communication with theinterior of the tube 49. It will be noted in FIG. 8 that a port 58places the chamber 57 in fluid communication with an annular chamber 59formed between the shaft 47 and the wall of the cylinder 43.

The third section cylinder unit 16 ('FIG. 8), includes a housing 61secured to the cylinder unit 14, and having a packing gland 62 at theforward end and a closed rear end 63. A shaft 64 is reciprocallyinserted in said housing 61 with a piston 66 at the inner end and across bar 67 at the outer end which is secured to the third section 13.

The housing 43 of the cylinder unit 14 is fluidly connected to thehousing 61 of the cylinder unit 16 by a conduit 68, fluid communicatingthe chamber 59 with a chamber 69 between the piston 66 and the packing6-2. Another conduit 71 connects the chamber 52 to a chamber 72 betweenthe piston 66 and the rear end 63. A relief valve 73 interposed in theconduit 71 permits fluid to flow through the conduit 71 in the directionof the arrows only after a certain pressure is attained. A check valve74 permits a flow of fluid in an opposite direction through the conduit71.

Referring to FIG. 9, a reservoir 76 for fluid is provided, and a pump 77is connected to the reservoir for pumping fluid through a control valve7 8 for transmission through a line 79 to the passage 54, orfortransmission through a line 81 to the passage 56. A by-pass line 82 isprovided.

With the apparatus 10 in the position of FIG. 4, operation to extend thesections is as follows. Fluid is pumped through line 81 and passage 56to the tube 49, whereupon the fluid enters the chamber 52. 'Fluidpressure therein forces the cylinder 43 away from the stationary piston47 until the second section 12 attains its extended position of FIG. 5.It will be noted that in this position, the latch 17 extends through theopening 39 partially due to engagement with the third section.

Continued fluid pressure in the chamber 52 overcomes the relief valve 73whereupon fluid enters the chamber 72 (FIG. 8) and the shaft 64 isforced outwardly of the cylinder 61, pulling the third sectin to theFIG. 6 position. As this occurs, the latch 17 is pulled completely intothe FIG. 6 position, whereupon the second section 12 is locked againstfurther movement.

During the extension process, fluid in the chambers 59, '7 and 69 isforced out thereof due to the diminishing size of the chambers, thefluid passing outwardly through the passage 54 and the line 79 fortransmission to the reservoir 76.

To retract the sections, fluid is redirected through the line 79 andpassage 54, and into the chambers 57 and 59. As the cylinder 43 cannotmove relative to the shaft 47, due to the cylinder 46 being locked tothe section 11, the fluid continues to flow through the conduit 68 intothe chamber 69. This forces the piston 66 rearwardly, pulling the shaft64 and the third section 13 back to the FIG. 5 position. The fluid inthe chamber 72 escapes out through the conduit 71, the check valve 74permitting the reverse flow, and into the chamber 52. From the chamber52, the fluid returns to the reservoir through the tube 49.

As the third section 13 engages the latch 17 and removes it from itslocking position, the fluid within the chamber 59 moves the piston 48and effects a retraction of the shaft 47 into the chamber 52, thuscompleting the retraction process.

In summation, a multiple extension apparatus is described and disclosedwhich provides a certain, positive, and sequential movement of thesecond section and third section out of the first section as a unit, andof the third section out of the second section, the retraction being theexact reverse of the extension operation.

Some changes may be made in the construction and arrangement of mymultiple extension apparatus without departing from the real spirit andpurpose of my invention, and it is my intention to cover by. my claims,any modified forms of structure or use of mechanical equivalents whichmay be reasonably included within their scope.

I claim:

1. A multiple extension apparatus comprising in combination: l

a first tubular section one end of which is closed and adapted to besecured to a structure, the other end of which is open;

a second tubular section having an open outer end and and a closed innerend wall and being slidably mounted in said first section;

a third tubular section slidably mounted in said second section;

first fluid actuated means including a cylinder mounted in said secondsection and secured thereto, and including a shaft reciprocalwithin-said cylinder and secured to said first section, said first meansoperable to move said first and second sections longitudinally .relativeto each other; i

second fluid actuated means including a cylinder mounted in said secondsection and operatively connected to said second section, and includingfurther a shaft reciprocal within said fluid means cylinder and securedto said third section, said second means operable to move said secondand third sections longitudinally of each other;

said first and second cylinders being positioned in side by siderelationship on said inner end wall of said second tubular section; and

control means for directing fluid under pressure to said first andsecond means.

2. A multiple extension apparatus comprising in combination:

a first tubular section one end of which is closed and adapted to besecured to a structure, the other end of which is open;

a second tubular section slidably mounted in said first section;

a third tubular section slidably mounted in said second section;

first fluid actuated means including a cylinder mounted in said secondsection and secured thereto, including a piston reciprocally mountedtherein, and including further a tubular shaft one end of which issecured to said piston and the other end of which is secured to saidfirst section;

a tube extended through said shaft and one end of which is open andextends through said piston, the other end being open at said shaftother end to the passage of fluid, a chamber formed between said tubeand said shaft, a second chamber formed between said shaft and saidcylinder on one side of said piston, said shaft having an opening formedtherein to fluidly communicate said chambers;

second fluid actuated means operatively connected to said second andthird sections and operable to move said second and third sectionslongitudinally of each other; and

control means for directing fluid under pressure to said first andsecond means.

3. A multiple extension apparatus comprising in combinationz a firsthollow section one end of which is adapted to be secured to a structure,and the other end of which is open;

a second hollow section slidably mounted within said first section andhaving an open end;

a third hollow section slidably mounted within said second section andhaving an open end;

first fluid actuated means including a cylinder mounted in said secondsection and secured thereto, including a piston reciprocally mountedtherein, and including further a tubular shaft one end of which issecured to said piston and the other end of which is secured to saidfirst section;

a tube extended through said shaft and one end of which isopen andextends through said piston, the other end being open at said shaftother end to the passage of fluid, a chamber formed between said tubeand said shaft, a second chamber formed between said shaft and saidcylinder on one side of said piston, said shaft having an opening formedtherein to fluidly communicate said chambers; and

second fluid actuated means including a cylinder mounted on said firstmeans, one end of which is in fluid communication with said first meanscylinder on one side of said piston and the other end of which is influid communication with said first means cylinder on the other side ofsaid piston, including further a piston reciprocally mounted within saidsecond means cylinder between the ends thereof, and including a shaftsecured at one end to said second means piston and at the other end tosaid third section externally of said second means cylinder.

4. A multiple extension apparatus comprising in combination;

a first hollow section one end of which is adapted to be secured to astructure;

a second hollow section slidably mounted in said first section;

a third hollow section slidably mounted in said second section;

first fluid actuated means operably connected to said first and secondsections and operable to move said first and second sectionslongitudinally relative to each other;

second fluid actuated means operably connected to said second and thirdsections and operable to move said second and third sectionslongitudinally of each other;

control means for directing fluid under pressure to said first andsecond means;

latch means secured to said first section for releasably locking saidsecond section to said first section in an extended position of saidsecond section; and

means on said third section for engaging said latch means when saidthird section is in its retracted position within said section sectionto prevent said latch means locking said first section to said secondsection.

5. A multiple extension apparatus comprising in combination:

a first tubular section one end of which is closed and adapted to besecured to a structure, the other end of which is open;

a second hollow section slidably mounted in said first section;

a third hollow section slidably mounted in said second section;

first fluid actuated means operably connected to said first and secondsections and operable to move said first and second sectionslongitudinally relative to each other;

second fluid actuated means operably connected to said second and thirdsections and operable to move said second and third sectionslongitudinally of each other;

control means for directing fluid under pressure to said first andsecond means;

said first section having an opening formed therein, and

said second section having an opening formed therein and alignable withsaid first section opening upon said second section attaining anextended position;

latch means secured to said first section and movable into said openingswhen aligned to releasably lock said first section and second sectionagainst relative movement; and

means on said third section to engage said latch means to preventlocking engagement ot said latch means with said opening in said secondsection when said third section is in its retracted position.

6. A multiple extension apparatus comprising in combination:

a first tubular section one end of which is closed and adapted to besecured to a structure, the other end of which is open;

a second hollow section slidably mounted in said first section; a

a third hollow section slidably mounted in said second section;

first fluid actuated means operably connected to said first and secondsections and operable to move said first and second sectionslongitudinally relative to each other;

second fluid actuated means operably connected to said second andthirdsections and operable to move said second and third sectionslongitudinally of each other;

control means for directing fluid under pressure to said first andsecond means;

said first section having an opening formed therein, and

said second section having an opening formed therein and alignable withsaid first section opening upon said second section attaining anextended position;

means including a latch pivotally mounted to said first section andmovable into said first and second sections through said openings whenaligned to releasably lock said first and second sections together, andincluding further a resilient element biasing said latch toward saidopenings; and

said third section having a portion disposed adjacent said opening insaid second section when said third section is retracted, said portionengaging said latch to pivot it out of locking engagement with saidopening in said second section.

References Cited by the Examiner UNITED STATES PATENTS 2,296,819 10/1942Osgood 91167 X 2,701,551 2/1955 Gunning 9141-2 2,709,368 5/ 1955 Wolpert92-2O X 2,984,373 5/196'1 Przybylski 2'1'255 3,119,455 1/1964 Fuehrer 9116'8 X FOREIGN PATENTS 875,882 7/ 1942 France.

1,1 12,668 11/ 1955 'France.

SAMUEL LEVI-NE, Primary Examiner. E. ENGELTHALER, Examiner.

3. A MULTIPLE EXTENSION APPARATUS COMPRISING IN COMBINATION: A FIRSTHOLLOW SECTION ONE END OF WHICH IS ADAPTED TO BE SECURED TO A STRUCTURE,AND THE OTHER END OF WHICH IS OPEN; A SECOND HOLLOW SECTION SLIABLYMOUNTED WITHIN SAID FIRST SECTION AND HAVING AN OPEN END; A THIRD HOLLOWSECTION SLIDABLY MOUNTED WITHIN SAID SECOND SECTION AND HAVING AN OPENEND; FIRST FLUID ACTUATED MEANS INCLUDING A CYLINDER MOUNTED IN SAIDSECOND SECTION AND SECURED THERETO, INCLUDING A PISTON RECIPROCALLYMOUNTED THEREIN, AND INCLUDING FURTHER A TUBULAR SHAFT ONE END OF WHICHIS SECURED TO SAID PISTON AND THE OTHER END OF WHICH IS SECURED TO SAIDFIRST SECTION; A TUBE EXTENDED THROUGH SAID SHAFT AND ONE END OF WHICHIS OPEN AND EXTENDS THORUGH SAI DPISTON, THE OTHER END BEING OPEN ATSAID SHAFT OTHER END TO THE PASSAGE OF FLUID, A CHAMBER FORMED BETWEENSAID TUBE AND SAID SHAFT, A SECOND CHAMBER FORMED BETWEEN SAID SHAFT ANDSAID CYLINDER ON ONE SIDE OF SAID PISTON, SAID SHAFT HAVING AN OPENINGFORMED THEREIN TO FLUIDLY COMMUNICATE SAID CHAMBERS; AND SECOND FLUIDACTUATED MEANS INCLUDING A CYLINDER MOUNTED ON SAID FIRST MEANS, ONE ENDOF WHICH IS IN FLUID COMMUNICATION WITH SAID FIRST MEANS CYLINDER ON ONESIDE OF SAID PISTON AND THE OTHER END OF WHICH IS IN FLUID COMMUNICATIONWITH SAID FIRST MEANS CYLINDER ON THE OTHER SIDE OF SAID PISTON,INCLUDING FURTHER A PISTON RECIPROCALLY MOUNTED WITHIN SAID SECOND MEANSCYLINDER BETWEEN THE ENDS THEREOF, AND INCLUDING A SHAFT SECURED AT ONEEND TO SAID SECOND MEANS PISTON AND AT THE OTHER END OF SAID THIRDSECTION EXTERNALLY OF SAID SECOND MEANS CYLINDER.